In a large reasonably heavy lidded soup pot saute onions in butter until translucent and just beginning to brown.Add carrots, stock and ginger. bring to a boil, reduce to simmer and cook till carrots are very soft.Add frozen orange juice and blend with hand blender or in blender.Add salt and tobasco to taste. Don't be shy with either I add a fair amount of each but taste after each addition.The amount of salt will naturally depend on whether your stock was salty or homemade. I use either.Also the amount of orange juice is to taste . This is just a starting point.I like enough Tobasco to taste a little kick.Yummy